Navigation working in Object mode but not Edit mode?
Yes, this happens when you use "LEFT" click selection (not the default).

the shortcuts you used above need the "emulate 3 button mouse" setting enabled... which you can do with "RIGHT" click selection:



but as soon as yu enable "LEFT" click selection, the setting is unavailable (greyed), and thus those shortcuts doesn't work anymore



I guess you're on Windows, and I suggest you to use a little utility (called X-mouse, or a similar one) I suggested in another answer, here;

Can&#39;t navigate in the 3d view

With that, you can have an automatic setup just for Blender mouse usage, and your 3 button mouse will use the middle button as it is intended by Blender, so you don't need the "emulate 3 button mouse" setting, and thus you don't need the shortcuts either...

hth